In the course of a growing season, modern plant culture dictates multiple treatments with fertilizer and pesticide, and in winter, where snow and ice are present for periods of time, proper property and equipment (e.g. aviation) maintenance requires the application of de-icing and anti-icing materials. A practitioner of plant culture must decide whether a particular treatment is best performed with a granular product or a liquid spray application. Crops as diverse as turf, grain crops, tubers, ground fruits and vegetables, and horticultural plantings are routinely treated with either granular or sprayed substances. Facility and equipment maintenance operations likewise employ either granular de-icers or liquid compositions, so a similar choice must be made by that practitioner. Each application method has limitations. Specifically, while granule broadcast tends to provide a simple broadcast, generally long-term release and safe handling, granules are difficult to adhere to plant and equipment surfaces, create concentration gradients about each granule, and represent an ongoing potential toxin or physical entity that can be inadvertently contacted or ingested by humans or fauna, or pose mechanical problems for equipment such as maintenance and aviation equipment. In contrast, spray treatment generally requires considerable skill for application, contacts only exposed foliage and equipment and surfaces receiving indirect drainage from other surfaces, and tends to dissipate, or “run off,” quickly. Some sprays such as anti-icers require the use of expensive polymers and additives in order to prolong the “holdover time,” or length of time the equipment may be allowed to stand ice free before it is put into service. Based on these treatment characteristics, pesticides targeting weed leaves or foliage-feeding pests and de-icers and anti-icers targeting equipment surfaces tend to be applied as a liquid spray, while fertilizers and pesticides targeting weed seeds, grubs and other soil-dwelling pests and de-icers and anti-icers targeting paved surfaces often are delivered as granules. Regardless of whether spray or granule broadcast is used, the application method is not completely satisfactory. For instance, spray application fails to reach pests dwelling on the underside of foliage and is quickly dissipated and leached into soil by rain, and liquid de-icers and anti-icers can cause environmental wastewater management problems because a significant excess amount of product must be used in order to allow for adequate contact time.
Granular pesticide formulations often require the use of additional pesticide due to inefficiencies in the timely release, or efficient environmental extraction, of the pesticide from the associated granular substrate materials.
Thus, there exists a need for a granule that, through foaming upon contact with water, has desirable attributes of both granule, broadcast and spray treatment for use in plant culture and/or in de-icing and anti-icing.
Additionally, the use of a foaming mechanism offers another tool for pest control, which may augment or replace the traditional pesticide material in certain cases. By generating a gas, along with a temporary containment for the gas, which may be directly toxic to, or which may alter the behavior of certain animal pests, the invention may serve as a pesticide or synergist in its own right.
The foaming mechanism as applied to de-icers can significantly enhance product distribution, adhesion, penetration of ice/snow cover, and separation of ice/snow from the treated surfaces due to the chemical and kinetic energy it provides. Likewise, the mechanism may enhance the use of exothermic energy (from dissolution of certain salts, e.g. calcium chloride).